fix: try two public urls for maintainer exists lint

[beckermr]

Checklist

• Added a news entry
• Regenerated schema JSON if schema altered (python conda_smithy/schema.py)

This PR fixes #2164 by using two public URLs to check if the maintainer exists instead of using the github API anonymously. Hopefully it is more robust since the anonymous API has pretty restructive rate limits.

[beckermr]

cc @jakirkham @h-vetinari

[beckermr]

@conda-forge/core this one is ready for review!

[h-vetinari]

Thank you!

[jaimergp]

Ah, I was about to suggest that we don't need a GET here, a HEAD is enough:

>>> requests.head("https://github.com/jaimergggggg").status_code
404
>>> requests.head("https://github.com/orgs/jaimergggggg/teams", allow_redirects=False).status_code
404
requests.head("https://github.com/jaimergp").status_code
200
>>> requests.head("https://github.com/orgs/jaimergp/teams", allow_redirects=False).status_code
404
requests.head("https://github.com/conda-forge").status_code
200
>>> requests.head("https://github.com/orgs/conda-forge/teams", allow_redirects=False).status_code
302

Note also that the org check returns 302, not 200. So the code should be:

        req_profile = requests.head(
            f"https://github.com/{maintainer}",
            allow_redirects=False,
        )
        is_user = req_profile.status_code == 200
        req_org = requests.head(
            f"https://github.com/orgs/{maintainer}/teams",
            allow_redirects=False,
        )
        is_org = req_org.status_code in (200, 301, 302) # just to be safe

[jaimergp]

cc @beckermr ^

[beckermr]

I'll follow up with these improvements in another pr.

[beckermr]

Thank you!